Let pyauto create an attached webdriver instance to manipulate web pages.

chrome/test/pyautolib/webdriver_factory.py

+#!/usr/bin/python

[Nirnimesh, 2011/08/01 19:21:24]

I see 'webdriver' and 'chromedriver' used interchangeably. Please pick one and
use throughout this file. Should the filename be chromedriver_factory.py?

[kkania, 2011/08/02 15:10:44]

changed to chromedriver

+# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Factory that creates WebDriver instances for pyauto."""
+
+import os
+import random
+import tempfile
+
+import pyauto_paths
+from selenium import webdriver
+from selenium.webdriver.chrome import service
+
+
+class WebDriverFactory(object):
+  """"Factory that creates WebDriver instances for pyauto.
+
+  Starts a single chromedriver server when necessary. Users should call 'Stop'
+  when no longer using the factory.
+  """
+
+  def __init__(self):
+    self._chromedriver_server = None
+
+  def NewWebDriver(self, pyauto):
+    """Creates a new remote WebDriver instance.

[Nirnimesh, 2011/08/01 19:21:24]

Why 'remote'?

[kkania, 2011/08/02 15:10:44]

The remote webdriver is the most configurable. The python bindings for the
ChromeDriver start and stop the chromedriver server for each session, which is
not what we want. The ChromeDriver is just a wrapper around the remote one
anyways.

+
+    This instance will connect to a new automation provider of an already
+    running Chrome.

[Nirnimesh, 2011/08/01 19:21:24]

nit: leave a blank line before Args: and Returns:

[kkania, 2011/08/02 15:10:44]

Done.

+    Args:
+      pyauto: pyauto.PyUITest instance
+    Returns:
+      selenium.webdriver.remote.webdriver.WebDriver instance
+    """
+    self._StartServerIfNecessary()
+    channel_id = 'testing' + hex(random.getrandbits(20 * 4))[2:-1]
+    if not pyauto.IsWin():
+      channel_id = os.path.join(tempfile.gettempdir(), channel_id)

[Nirnimesh, 2011/08/01 19:21:24]

where does this file reside on linux?

[kkania, 2011/08/02 15:10:44]

http://docs.python.org/library/tempfile.html#tempfile.tempdir

+    pyauto.CreateNewAutomationProvider(channel_id)
+    return webdriver.Remote(self._chromedriver_server.service_url,
+                            {'chrome.channel': channel_id})
+
+  def _StartServerIfNecessary(self):
+    """Starts the ChromeDriver server, if not already started."""
+    if self._chromedriver_server is None:
+      exe = pyauto_paths.GetChromeDriverExe()
+      if exe is None:

[Nirnimesh, 2011/08/01 19:21:24]

assert exe, 'Cannot find chromedriver exe. Did you build it?'

... will produce equivalent effect

[kkania, 2011/08/02 15:10:44]

Done.

+        raise RuntimeError('Cannot find chromedriver exe. Did you build it?')
+      self._chromedriver_server = service.Service(exe)
+      self._chromedriver_server.start()
+
+  def Stop(self):

[Nirnimesh, 2011/08/01 19:21:24]

Should the destructor call Stop() automatically to prevent a pileup of
chromedriver processes?

[kkania, 2011/08/02 15:10:44]

It could, but since __del__ isn't called until the garbage collector runs, I
wanted the client to make sure they shut it down properly themselves. Do you
want me to add it?

[Nirnimesh, 2011/08/02 18:07:13]

Yes please

__del__ is guaranteed to get called when your object goes out of scope, or is
deleted.

[kkania, 2011/08/02 23:19:19]

Done.

+    """Stops the ChromeDriver server, if running."""
+    if self._chromedriver_server is not None:

[Nirnimesh, 2011/08/01 19:21:24]

Add: self._chromedriver_server = None after this line

[kkania, 2011/08/02 15:10:44]

Done.

+      self._chromedriver_server.stop()